2020 Volume 91 Issue 4 Pages 411-416
In order to clarify the calf growth and reproductive performance of the cows in the year-round grazing system for cows with their calves in a cold region, a survey was conducted at K farm, where practiced the year-round grazing system for cows with their calves of Japanese Black in the northern Tohoku region. A total of 24 calves were weighed monthly for two years. The reproductive performance of cows was analyzed by browsing the reproductive records. The pasture was highly dominated by Kentucky bluegrass (Poa pratensis L.). The calves were supplemented with grass silage and concentrate diet in summer as well as corn silage in winter. The average daily gain in calves up to 9 months of age was 1.07kg/day for males and 0.94kg/day for females. For calves born in winter (from December to February), the average daily gain was 1.13kg/day for males and 0.93kg/day for females. The mean and median calving intervals were 410 and 384 days, respectively. In the year-round grazing system for cows with their calves in the northern Tohoku region, the growth performance of calves was enough, and the reproductive performance of cows was not inferior to the national average.
